Window ventilators

ABSTRACT

A window ventilator for a vehicle such as an automobile, comprises a sheet of transparent material such as glass or a plastics material, said sheet having formed therein a plurality of ventilation holes preferably by a moulding operation. The axes of the holes rise from the outside to the inside of the sheet relative to the fitment of the sheet in a window frame, the angle of inclination of said axes preferably being of the order of 45* to 55*.

O United States Patent [151 3,659,516

MacDonald [451 May 2, 197 2 s4] WINDOW VENTILATORS 3,083,630 4/1963Thaxton ..9s/2.2

[72] Inventor: Alastair Rigg MacDonald, 39 ClCUCh FOREIGN PATENTS ORAPPLICATIONS Gardens, Clarkston, Renfrewshire, Scotland 743 10/1887Great Britainj ..98/88 L [22] Flled: 1969 Primary Examiner-Meyer Perlin[21] App]. No.: 864,753 Assistant ExaminerW. C. Anderson Att0rneyYoung &Thompson [52] U.S. Cl ..98/2.l2 51 Int. Cl ..B60h 1 24 [571 ABSTRACT[53] Field Search "98/21, 88 L, 921 A window ventilator for a vehiclesuch as an automobile, com- 98/90' 71! 296/94; 244/121 prises a sheet oftransparent material such as glass or a plastics material, said sheethaving formed therein a plurality of ven- [56] References cued tilationholes preferably by a moulding operation. The axes of UNITED STATESPATENTS the holes rise from the outside to the inside of the sheetrelative to the fitment of the sheet in a window frame, the angle of376,844 1/1888 Appert ..98/96 inclination f said axes f bl being f theorder f 45 to 1,560,585 ll/l925 Klingberg... 55 2,557,442 6/1951 Kurilo2,850,087 9/1958 .Ianaman ..98/2.2 1 Claim, 2Drawing Figures wmuowVENTILATORS This invention relates to improvements in windowventilatOlS.

More particularly, the invention relates to a window ventilator for amobile vehicle such as a motor car, lorry or railway carriage, saidventilator also sewing as a demister.

There has previously been proposed a window ventilator consisting of asingle sheet of transparent material of shape and dimensions such thatit can be fitted within the frame of a particular window to beventilated and formed with a plurality of downwardly and outwardlyinclined ventilating holes. In this prior proposal the inclination ofthe holes relative both to the hole cross-sections and to the sheetthickness has been insufficient to preclude unimpeded flow of airthrough the holes in the sheet from the direction of the exterior andnormal to the plane of the sheet. As a result an unpleasant whistlingnoise is produced when a vehicle fitted with the ventilator is in rapidmotion.

The present invention is characterized in that the lower edge of eachhole at the inner surface of the sheet is on at least as high a level asthe upper edge of the same hole at the outer surface of the sheet whenthe sheet is in place within the window frame. Consequently, flow of airthrough the holes in the sheet from the direction of the exterior andnormal to the plane of the sheet is precluded, and there is nounpleasant whistling noise when a vehicle fitted with the ventilator isin motion.

Preferably the angle of inclination of said holes is 45 to 55 to thenormal to the sheet.

Further preferably, the holes are located in two or more lines, oneabove the other.

In a preferred embodiment the holes are of constant diameter throughouttheir length.

In another embodiment the holes are venturi-shaped.

An embodiment of the invention will now be described, by way of example,with reference to the accompanying drawing, in which:

FIG. 1 is a front elevation of a window ventilator according to theinvention; and

FIG. 2 is a vertical, transverse section through a major part of theventilator on an enlarged scale.

Referring to the drawings, a window ventilator and demister consists ofa sheet 1 of a thermosetting transparent plastics material shaped forremovable fitment within the top portion of a car window frame (notshown). The sheet is produced by an injection moulding process and themould shape is tailored to the shape of the upper part of the window ofthe particular make and model of car for which the sheet is intended.The sheet 1 is provided with two horizontal linesof inclined holes 2.Said holes 2 are of constant diameter throughout and extend through thesheet 1 at an angle of 45 to 55 to the normal, rising from the outside 3to the inside 4 of the sheet 1.

The positioning of the holes 2 is an important factor in achievingmaximum ventilation efficiency. They should extend through the sheet ina plane normal to the upstanding sheet. If the holes are directedtowards the rear of the vehicle rain water will tend to penetrate intothe interior of the vehicle through the holes and if they are directedtowards the front of the vehicle very little air will pass through theholes. Furthermore, if the holes are drilled straight through the sheethorizontally, with no inclination, an unpleasant whistling noiseresults.

Experiments have shown that no whistling occurs when the angle ofinclination to the horizontal of the holes is 45 to 55. Variations ofthis angle are possible without whistling occurring. The minimum angleof inclination to avoid whistling varies according to different makes ofcar and can be determined readily by simple testing.

The perimeter of the ventilator sheet is shaped to fit tightly into thegrooving of the car window frame. The under edge of the sheet isfurthermore shaped to conform exactly to the upper edge of the carwindow rabbetted so that the window can be raised into contact with thesheet with no gap existing between them'to cause draughts. The upperedges of car windows are 'quite often convex in shape and thus the loweredge of the ventilator sheet would be correspondingly shaped to allowthe sheet to be properly sealed and seated.

In the case of frameless windows, i.e. no channelling being provided onthree sides of the window, the ventilator sheet would be provided withbracket fittings for securing the sheet to the quarter light channel.

The ventilator sheet of the invention provides for a natural flow offresh air to the interior of the vehicle without causing any draught ornoise. By virtue of the rising angle of the ventilation holes, airentering the vehicle is directed against the roof, resulting in uniformventilation with no unpleasant draught streams.

Maximum efficiency is obtained by fitting a set of four ventilatorsheets to the vehicle, but adequate ventilation is achieved by fitting apair of sheets. The quantity of ventilating air drawn into the carthrough the ventilator sheet can be controlled by varying the degree ofopening of the quarter light window of the car.

In a modification, the holes are formed by drilling through a pre-shapedsheet of glass or transparent plastics material.

A modified version of the ventilator sheet, suitable for us in hotclimates, has venturi-shaped holes to provide forced ventilation byvirtue of the venturi action. Such a sheet would be produced by amoulding process.

A particularly advantageous application of the ventilator sheet is tohovercraft, where spray presents a serious problem with regard toventilation. It has been proposed to fit ventilating means in the widewindows near the roof of hovercraft to overcome this spray problem.Installation of the ventilator sheets of the invention would be oneanswer to the problem, as spray would not pass through the ventilationholes to the interior of the craft.

The principle of the vents is to provide fresh air without draughts. Itis not intended to compete with any fresh air system which is a built-infixture on the car but is ancillarly to such a fresh air system. Thevents are as aforesaid most effective with the use of quarterlightfittings on the front side windows. The principle is as follows:

Most systems of heating a car draw hot air from below, which rises totop or roof of the car, with the result that passengers and driver arebreathing foul air, without any fresh air ventilation. To enable freshair to enter, side windows are open, and sometimes the forward quarterlights are used, or, as often as not, the drivers window is lowered withthe resultant effect of air being drawn in, in large quantities, andcausing a draught which by-passes the driver, and sweeps round the backof the car to the passengers, and finally striking the person sittingbeside thedriver. The ventilation sheets work in the following way:

By means of opening the quarter lights, a pleasant flow of air throughthe sheets is projected to strike the roof of the ear, and carries thefoul air out through the quarter lights, thus preventing a build-up ofwarm foul air. The flow of air is controlled by the quarter-lightfitting and maximum efficiency is attained at a point between a quarterand a third open. When the quarter lights are closed, virtually no airis allowed into the car through the ventilation sheets. An additionalfeature is that there is no wind whistle, due to the angle of the holes,which decreases road noise, and minimizes drumming. Furthermore, testshave shown that steaming-up of windows is very much decreased when thecar is in motion.

OPERATION OF SYSTEM Warm air can be drawn in by the car-heating systemto the interior of the car, but fresh air drawn in through theventilator sheets is circulated around the roof with the quarter lightsopen. To clear the rear window which has steamed up when the car isstationary, cold air is projected to the windscreen by the cars coldsystem. This forces the air which is drawn in through the ventilationsheets towards the rear window, which clears quickly. After the'rearwindowtis clear, hotairmay be projected into the interior of the car. Itis of importance to not thatduring heavy rain, it is not required todrive with any=windows open, only the quarter lights.

Anyone sitting smoking in the front of the car will find that, onopening the quarter light, the smoke is expelled immediately, and doesnot circulate throughout thecar, or from side to side. 7

As described above, the ventilatorsheetsare constructed of transparentplastics material, and one fitted into the existing -window rails, andonce "in place, the window-isclosed. "If desired, the window may beopened while the ventilator sheets remain in position at the top of thewindow'sash by virtue of the window channels'which hold the sheets.Thus, full use of the window is still obtained. No mechanical partsare'involved and-moreover no electric motive power is required tooperate the ventilator sheets.

I claim:

l.-A-window ventilator consisting of a single sheet of transparentmaterial of shape and dimensions such that it can be fitted within theframe of a particular window to be ventilated and: formed with aplurality of downwardly and outwardly inclined ventilating holescharacterized in that the lower edge of each holevat the inner surfaceof the sheet is on at least as high a level as theupperedge-ofv the samehole at the outer surface'of the sheet when the sheet is in place in'the frame, the diameters otthe holes being so related to the thicknessof the sheet thatthe angle of inclinationof the'holes'is within therange of to to the plane of the sheet.

1. A window ventilator consisting of a single sheet of transparentmaterial of shape and dimensions such that it can be fitted within theframe of a particular window to be ventilated and formed with aplurality of downwardly and outwardly inclined ventilating holescharacterized in that the lower edge of each hole at the inner surfaceof the sheet is on at least as high a level as the upper edge of thesame hole at the outer surface of the sheet when the sheet is in placein the frame, the diameters of the holes being so related to thethickness of the sheet that the angle of inclination of the holes iswithin the range of 45* to 55* to the plane of the sheet.